Method and apparatus for drying printing ink



Aug. 23, 1938.. R. HELMER 2,127,956

METHOD AND APPARATUS FOR DRYING PRINTING INK Filed Dec. 26. 1935 3 Sheets-Slieet 1 INVENTOR ATTORNEY /m was R. HELMER Aug. 23, 1938.-

LZETHOD AND APPARATUS FOR DRYING PRINTING INK Filed Dec. 26. 1935 3 Sheets-Sheet 2 ATTORNEY MENTOR R. HELMER METHOD ANIS APPARATUS FOR DRYING PRINTING INK Filed Dec. 26, 1935 3 Sheets-Sheet 3 INVENTOR ATTORNE Patented Aug. 23, 1938 PATENT OFFICE METHOD AND APPARATUS FOR PRINTING INK DRYING Robert Helmer, Douglaston, N. Y., assignor to The International Printing Ink Corporation, New York, N. Y., a corporation of Ohio Application December 26,1935, Serial No. 56,244

12 Claim.

heat to the paper on which the 'ink has been printed to raise the paper and ink to a temperature of about 150 C. This temperature is will- 15 cient to vaporize the solvent in the ink and insufflcient to injure the paper. In carrying out this method, it has been customary to heat the paper from the back or unprinted side, usually, by contact with a solid heat-conducting member so such as a hot metal drum, or by means of hot air. In both cases, the temperature of the heating means (hot drum or hot air) has been limited to a temperature which cannot injure the paper. This limitation of the temperature of the heatgg applying means makes. it necessary to apply the heat for a substantial period in order to raise the paper and the ink to the temperature at which the solvent in the ink is highly volatile and to volatilize the solvent.

I have discovered that, on the application of intense heat to printed matter consisting of paper printed with a quick drying ink of the type referred to, the period of time required to raise the solvent in the ink to the temperature at 35 which it volatilizes rapidly and to volatilize substantially all of the solvent in the ink is materlaliy shorter. than the time required to char or burn the paper. My method consists in drying printing ink by the'application to the printed 40 matter of a heat so intensethat it is capable of raising the temperature of the paper far above its scorching point, while at the same time limiting the period of the application of such heat to a time which is sufficient to volatilize substan- 45 tially all of the solvent of the ink and less than the time which would be required to char or burn the paper. The heat applied in this method may be above the ignition point of the vapor of the ink solventfso that at least some of the solvent 50 vapor from the ink is ignited and burned, but

neither the paper nor the binder in the ink which binder may be highly inflammable is burned or otherwise injured.

In accordance with my invention, the intense 55 heat is applied to the printed surface of the printed matter in the form of hot gas or radiant heat, or most desirably both, and the period of application of the heat to each part of the surface of the printed matter is limited by relative movement between the heat-applying means and the printed matter. I

My invention includes also apparatus by means of which my method may be carried out emciently and safely.

In the form which I now consider most desira- 1o ble, the apparatus includes a closed furnace, one wall of which is provided by a traveling web of paper bearing the ink to be dried. The opposite wall of the furnace carries the heat-applying means which direct an intense heat against 4 the printed surface oi the web. This wall is so arranged that it may be opened to direct the heat-applying means away from the web in order to avoid scorching the web when the web is stationary. The'opening means are most desirably operatively connected with the means for causing the travel of the web across the furnace in such a way that opening of the furnace occurs automatically when the movement of the web is stopped.

A specific embodiment of the apparatus features of my invention is illustrated in the accompanying drawings, in which Fig. 1 is a side elevation of the complete apparatus, omitting parts of the printing press which are of standard construction and showing the furnace in longitudinal section;

Fig. 2 is a diagrammatic view containing an enlarged side elevation of the furnace taken from the opposite side from Fig. 1 and an enlarged side view of the means for supplying gas and air to the furnace, and showing the electrical connections;

Fig. 3 is an enlarged transverse section of the furnace taken on the line 3-3 of Fig. 1;

Fig. 4 is a further enlarged section taken on the line l-4 of Fig. 3 and showing the details of one of the burners, and indicating in dotted lines the position of this burner when turned away from the web;

Fig. 5 is an enlarged section taken on the line 5-5 of Fig. 1, showing the air control valve, and

Fig. 6 is a diagram of the electric control.

The apparatus illustrated includes a printing press. iii of standard construction for printing on a web P of paper. Ink is applied to the web of paper P in the press. The web'emerges from the press over a roller H with its printed side uppermost, and, after the drying of the ink by 66 the apparatus to be described, the web P is wound up on a rewind roller I2 which constitutes a part of the printing press. The rewind roller and the other rollers of the press are driven by a threephase electric motor indicated diagrammatically at l3 in Fig. 2. The customary means are provided for regulating the speed of the press which determines the speed of travel of the web P.

In its travel between the guide roller I I of the press and the rewind roller I2 of the press, the web P passes over guide bars I4 and rollers I5, l6, II, l6 and I9 mounted on a frame 20.

A furnace 30 is mounted on horizontal bars 2| of the frame 26 above and adjacent to a portion of the web traveling between the rollers II and IS. The furnace is enclosed by side walls 3|, end walls 32, 32'". a top wall 33, and the portion of the web P between the end walls 32 which constitutes the bottom wall of the furnace. The end walls 32 and 32 terminate a short distance above the surface of the web. The top wall 33 contains three doors 34, which carry series of radiant gas burners 35 which are directed towards the web P when the doors 34 are closed. Each row of burners 35 is mounted on a pipe 36. Each pipe 36 is attached at one of its ends to a supply pipe 31 through a stuffing box 36 in such manner that each pipe 36 may be rotated about its own axis. Each pipe 36 thus serves as a pivot about which one row of burners 35 and one door 34 may be rotated between a position in which the doors are closed and the burners are directed towards the web P (shown in full lines in Figs. 1, 3 and 4 and in dotted lines in Fig. 2) and a position in which the doors are open and the burners are directed away from the web (shown in dotted lines at the top of Fig. 2 and in dotted lines in Fig. 4).

Means are provided for simultaneously opening and closing the three doors 34 and for swinging the three rows of burners 35 away from and towards the web. Such means include radial arms 66 fixed on the pipes 36, and connected by links to a swinging bar I provided with a handle I0, so that, when the bar I0 is in the position shown in full lines in Fig. 2, the pipes 36 are turned so as to close the furnace and direct the burners towards the web P and, when the bar I0 is swung to the position shown in dotted lines in Fig. 2, the pipes are turned into a position in which the furnace is open and the burners are turned directly away ,from the web.

Each of the burners 35 includes a nipple 39, a deflector 40, and a parabolic radiator 4| of refractory material which is heated to incandescence by the gas flame issuing from the nipple and serves to direct the flame and radiant heat along the axis of the burner and, therefore, dirc :tly, against the web when the burner is turned towards the web, as shown in Fig. 4.

A mixture of gas and air is supplied to the burners through the pipes 36 and supply pipes 3I from a mixing chamber 42. The gas and air are supplied under pressure to the mixing chamher and the burners by a centrifugal pump 43, which draws air from the atmosphere through a pipe 44 and gas from a gas main 45.

After passing under and across the furnace 30, the web P passes through a suction duct 50 formed by an upper wall a lower wall 52, an end wall 53, and the end walls 32 of the furnace. The suction duct 56 is open at one side of the furnace and at the other side is connected to a conduit 54 containing an exhaust fan (not shown).

When the furnace is closed, the burners 36 direct intense heat toward the printed surface of the web P, which would char and burn the web if any portion of the area of the web were exposed to it for more than a very brief period of time. It is, therefore, essential that this supply of intense heat to the web be stopped when the'movement of the web is stopped. This may be accomplished in the form of apparatus illustrated by rotating the pipes 36 to open the doors 34 and direct the burners away from the web. It is desirable that automatic means should be provided for opening the furnace when the web is stationary and closing it when the web is put in motion. Such means are illustrated in Fig. 2 and Fig. 6.

Fig. 2 shows diagrammatically the main switch 66 of the press I0 which serves to connect the motor l3 of the press with supply lines 6|. When the switch 60 is open, the web is stationary and, when the switch 60 is closed, the web is put in motion by the motor I3 which drives the rewind roller I2 and the other rollers of the press.

The closing of the switch 66 energizes a control circuit 62 having two parallel branches one of which, 63, controls a small motor 66 carrying a pinion meshing with a gear I3 fixed on the middle one of the pipes 36. When the circuit 63-is energized by closing the switch 66 with the furnace open, the motor 66 acting through the gear I3 turns all the pipes 36 to swing the burners downward towards the web and to close the doors 34. Thus, the furnace is closed and the burners directed towards the web when the web is put in motion by closing the switch 66 and energizing the motor l3. If the web is stopped by opening the switch 60, or by any means cutting off the current from the motor I3, the circuits 62 and 63 are tie-energized. This causes operation of the motor 66 in the reverse direction to open the furnace and direct the burners away from the web.

Details of the mechanism which controls the motor 66, are shown in Fig. 6. The circuit 63 contains an electro-magnet 61 and this magnet and a spring 68 control the position of a reversing switch 69 connected between the motor 66 and a supply line 90. Rotation of the motor 66 in either direction beyond the points at which it directs the burners towards and away from the web is prevented by the opening of switches 8|] controlled by cams 6| mounted on the middle pipe 36.

In order to save fuel, it is desirable that the supply of gas to the burners be reduced when the furnace is opened. For this purpose, an automatic electric valve I5 of standard construction is placed in the gas supply pipe and connected in a branch 16 of the circuit 62. The valve I5 is opened only when the circuit I6 is energized. Closing of the valve I6 by deenergizing the circuit I6 also closes a butterfly valve IT in the air pipe 44 which is connected to the mechanism of the valve I5 by a link 18. To prevent extinguishment of the burners when the valves I5 and II are closed, a small by-pass I6 is provided around the valve 15 and a small opening 60 is provided in the butterfly valve II. This by-pass and this opening insure a sufficient supply of air and gas to the burners to keep them ignited and the refractory radiators incandescent when the web is stationary and the burners are turned away from the web.

A specific example of the practice of my method by means of the apparatus as described is as follows: An ink whose vehicle consists of a solution of a binder such as nitrocellulose in a volatilizable solvent such as diethylene glycol monobutyl ether or diethylene glycol monobutyl ether acetate is applied to the upper surface of the web P in the press to. As each successive part of the web is drawn through the furnace 30, intense gaseous and radiant heat are directed against the printed surface of the web by the radiant gas burners 35. The solventin the ink is vaporized and ignited as the web passes through the furnace. The products of combustion are drawn out of the furnace under-the end wall 32' and through the suction duct 50, so that they do not contaminate the air of the press room. Any vapor which may come off the web after it leaves the furnace is also drawn out through the duct 50. Although combustion, both of fuel gas and of the solvent vapor, is constantly taking place in the furnace, the paper web is not burned, charred or injured in any way because the period during which any area of the web is within the furnace is extremely short, amounting in practice to about one-third of a second. The paper of the web is, of course, heated to a considerable extent during the passage of the web across the furnace and the tensile strength of the web might be reduced if the web were allowed to remain hot. The web is, however, cooled during its passage over the rollers i6, i1, i8 (which are preferably water-cooled rollers) before it is wound up on the rewind roller l2. When the travel of the web is stopped for any reason, the furnace is immediately opened and the burners are directed away from the web so that the web is not burned.

In the apparatus described, the radiant burners 35 apply intense heat to the web both in the form of radiant heat and in the form of hot gas. This causes a very rapid volatilization of any volatilizible solvent contained in the ink. If the solvent is inflammable, a considerable part of it is ignited and burned in the furnace. The prodnets of combustion, as well as any part of the solvent vapor which is not burned, are drawn off through the suction duct 50 to a point remote from the web.

It is not essential that both radiant heat and gaseous heat be used. I have found it satisfactory to use gaseous heat only, but in this case burners ejecting large gas flames under heavy pressure are used and substantially all the solvent which is driven from the ink on the web is ignited and burned.

The drying of the ink by this method is extremely rapid and permits use of the method with rotary presses operating at a speed of 400 feet per minute.

My invention is by no means limited to the use of the method or the apparatus with the particular ink which has been mentioned for the sake of illustration; It has proved effective by drying and accelerating the, drying of many types of inks, including several which cannot be satisfactorily dried by the hot roll method.

What I claim is:

1. Apparatu; for drying printing ink comprising the combination with means for causing a traveling movement of a web of paper to which the ink has been applied, 01' an enclosed furnace located adjacent to the printed side of the web so that the web forms one side of the furnace, and means for opening the opposite wall of the furnace.

2. Apparatus for drying printing ink comprising means for causing a traveling movement of a web to which the ink has been applied, a turnably mounted heater located adjacent to the web, and means operatively connected with the means for causing. travel of the web for directing said heater towards the web when the web is in motion andaway from the web when the web is stationary. v

3. Apparatus for drying printing ink comprising means for causing a traveling movement of a web of paper to which the ink has been applied, an enclosed furnace located adjacent to the printed side of the web so that the web forms one wall of the furnace, and an automatic means for opening the opposite wall of the furnace when the traveling movement of the web is stopped.

4. Apparatus for drying printing ink comprise ing the combination with means for causing travel of a web to which the ink has been applied, of a gas burner located adjacent to a point of the travel of the web and mounted for rotation about an axis transverse the path of the web so that it may be directed towards or away from the web.

5. Apparatus for drying a printing ink comprising a combination with means for causing the travel of a web to which ink has been applied, of a heater adapted to apply intense heat to the printed side of the web at a point in its travel, said heater being mounted for rotation about an axis transverse the path of the web so that it may be directed towards or away from the web.

6. In a web printing press, apparatus for drying printing ink comprising means for causing a traveling movement of the web to which the ink has been applied, a movable heater, and means operatively connected with the means for causing travel of the web for moving said heater to an operative position when traveling movement is imparted to said web so that intense heat is directed upon the printed surface of the web and to an inoperative position when the movement of said web is stopped.

7. Apparatus for drying printing ink comprising the combination with means for causing a traveling movement of the material to which the ink has been applied, of a furnace, a heater attached to one wall of the furnace and adapted to direct intense heat upon the printed surface of the material, and automatic means for opening the furnace wall to which said heating element is attached.

8. Apparatus for drying printing ink comprising the combination with means for causing a traveling movement of a web to which the ink has been applied, of an enclosed furnace having a heating compartment and a separate suction compartment located adjacent to the printed side of the web so that the web forms'one wall of the furnace.

9. The method which comprises printing at room temperature with an ink containing a combustible binder dissolved in a volatilizable and inflammable solvent which is substantially nonvolatile at room temperature, and then applying to printed ink through a gaseous medium heat of sufficient intensity to volatilize the ink solvent instantaneously and ignite the solvent vapor, and limiting the time of application of said heat to a period so short that the heat does not char the ink binder.

10. The method which comprises printing on a combustible material with an ink containing a combustible binder dissolved in a volatilizable and inflammable solvent which is substantially non-volatile at room temperature, moving the printed material away from the printing means, applying through a gaseous medium to the print ed surface of the material heat of sufllcient intensity to volatilize the solvent and ignite the solvent vapor, maintaining the material out of contact with any heated surface between printing and the application of said heat, and limiting the time of application of said heat to each part of this surface of the material to a period so short that the heat does not char the material and the ink binder deposited thereon.

11. Apparatus for drying printing ink, comprising means for causing a traveling movement of a combustible web to which the ink has been applied, an enclosed furnace located adjacent to the traveling web so that its printed side is exposed to the furnace heat, means for maintaining the furnace temperature above the combustion temperature of the web, and means operatively connected. to the means for causing travel of the web for reducing the furnace temperature to a temperature below the scorching temperature of the web when the traveling movement of the web is stopped.

12. Apparatus for drying printing ink, comprising the combination with means for causing a traveling movement of the material to which the ink has been applied, of a plurality of rows of heaters adapted to direct intense heat toward the printed side of the material, each of said rows being mounted for rotation about an axis parallel with the axis of rotation of each other row so that the heaters may be directed toward or away from the material, said axes all lying in a plane parallel to the printed surface of said material.

ROBERT HELLER. 20

CERTIFICATE OF CORRECTION Patent No. 2,127,956.

ROBERT HELPER August 25, 1958.

It is hereby certified that the name of the assignee in the above numbered patent was erroneously described and specified .as The International Printing Ink.Corporation" whereas said name should have been described and specified as Interchemical Corporation, New York, N. Y., a corporation of Ohio, as shownby the record of assignments in this office; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 18th day of April, A. o. 1959.

Henry Van Arsdale (Seal) Acting Commissioner of Patents.

DiSCLAiMER 2,127,956.R0bert Helmer, Douglaston, N. Y. METHOD AND Armazxros FOR DRYING PRINTING INK. Patent dated August 23, 1938. Disclaimer filed May 14, 1940, by the asslgnec, Interchemical Corporation.

Herebg enters this disclaimer to claims 4, 5, and 12 of said Letters Patent.

I ficwl Gazette June 4, 1940.] 

